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                                                                    Exhibit 31.1


                      CERTIFICATION PURSUANT TO SECTION 302
                        OF THE SARBANES-OXLEY ACT OF 2002
  (PURSUANT TO RULE 13A-14 OF THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED)

I, Thomas C. O'Brien, certify that:

1.   I have reviewed this report on Form 10-Q of Insurance Auto Auctions, Inc.;

2.   Based on my knowledge, this report does not contain any untrue statement of
     a material fact or omit to state a material fact necessary to make the
     statements made, in light of the circumstances under which such statements
     were made, not misleading with respect to the period covered by this
     report;

3.   Based on my knowledge, the financial statements, and other financial
     information included in this report, fairly present in all material
     respects the financial condition, results of operations and cash flows of
     the registrant as of, and for, the periods presented in this report;

4.   The registrant's other certifying officer(s) and I are responsible for
     establishing and maintaining disclosure controls and procedures (as defined
     in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over
     financial reporting (as defined in Exchange Act Rules 13a-15(f) and
     15d-15(f)), for the registrant and have:

     a)  Designed such disclosure controls and procedures or caused such
         disclosure controls and procedures to be designed under our supervision
         to ensure that material information relating to the registrant,
         including its consolidated subsidiaries, is made known to us by others
         within those entities, particularly during the period in which this
         report is being prepared;

     b)  Evaluated the effectiveness of the registrant's disclosure controls and
         procedures and presented in this report our conclusions about the
         effectiveness of the disclosure controls and procedures, as of the end
         of the period covered by this report based on such evaluation; and

     c)  Disclosed in this report any changes in the registrant's internal
         control over financial reporting that occurred during the registrant's
         first fiscal quarter that has materially affected, or is reasonably
         likely to materially affect, the registrant's internal control over
         financial reporting; and

5.   The registrant's other certifying officer(s) and I have disclosed, based on
     our most recent evaluation of internal control over financial reporting, to
     the registrant's auditors and the audit committee of the registrant's board
     of directors:

     a)  All significant deficiencies and material weaknesses in the design or
         operation of internal control over financial reporting which are
         reasonably likely to adversely affect the registrant's ability to
         record, process, summarize and report financial information; and

     b)  Any fraud, whether or not material, that involves management or other
         employees who have a significant role in the registrant's internal
         controls over financial reporting.

Date: November 9, 2005                /s/ Thomas C. O'Brien
                                      ------------------------------------------
                                      Thomas C. O'Brien, Chief Executive Officer